Machine for applying nuts to bolts



Dec. 15, 1925. 1,565,685

. H. THOMAS MACHINE FOR APPLYING NUTS T0 BOLTS Filed Nov. 20, 1920 Patented Dec. 15, 1925.

- UNITED STATES HANSON THOMAS, OF PITTSBURGH, IPENNSYLVANIA.

MACHINE FOR APPLYING NUTS TO BOLTS.

Application filed November 20, 1920. Serial" No. 425,446.

To all whom it may concern:

Be it known that I, HANSON THOMAS, a citizen of the United States, and resident of Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Machines for Applying Nuts to Bolts; and I do hereby declare the following to be a full, clear, and exact description thereof.

My invention relates to machines for applying nuts to bolts.

In nut and bolt factories the bolts are almost invariably shipped with the nuts screwed thereon, and in the case of track-bolts for railroad use the specifications of the different railways specify in all cases that the nuts must be screwed on the bolt to the extent of three or four turns of the nut, and the resistance offered to the further turning of the nut must be such that further turning cannot be done by the hand but can only be accomplished. by a wrench. The inspector, on examining the bolt, can tell whether the nut has been turned the proper number of turns by the fact that the bolt will extend about half way through the nut, indicating that it has been screwed up the proper amount. Furthermore these nuts, as applied to track-bolts, must be capable of being unscrewed by hand when they are to be used to obviate the necessity of using a wrench for. this purpose.

The object of my invention is to provide a machine by which nuts may be screwed on bolts so that the distance the nuts are screwed on and their tightness of fit will conform with the strict requirements of the above specifications, and by which the screwing-on pressure having been predetermined, the further screwing-0n of the nut will be stopped just as soon as the resistanceoffered is greater than said screwing-on pressure.

In the drawings, Fig. 1 is a longitudinal elevation partly in section ofa machine for applying nuts to bolts embodying my invention; Fig. 2 is an enlarged detail of the scale; for controlling the screwing-on pressure; and Figs. 3 and 4 show a modified form of my invention. t v

I have illustrated my-present invention in connection with a machine for applying nuts to bolts illustrated and described in my Patent No. 1,431,493, issued October 10, 1922. This application is in part a continnation of the application for said patent. As many of the parts of said machine have nothing to do with the present invention, I have not deemed it necessary to illustrate and describe all the parts of said machine in detail. I

The numeral 2 designates a suitable bedplate or base on which the parts composing the machine are mounted.

A shaft 3 is journaled in suitable bearings 4 in standards 5. A pulley 6 on the shaft 3 is connected up to any suitable source of power, although it is apparent that the machine may be driven by an electric motor if desired.

Mounted on the shaft 3 is the spur-pinion 7 which meshes with the gear-wheel 8 mounted on the shaft 9 mounted in suitable bearings. A bevel-pinion 10 on the shaft 9 engages bevel-pinion 11 on the shaft 13.

Mounted on the shaft 13 is a cam 15, which engages the roller 16. The roller 16 is carried by the slide-block 19 mounted in the guide 17. The slide-block 19 has the downwardly extending portion 20 which is connected by the fork 21 of the lever 22 pivotally mounted at 23 in the base 2.

-The block 19 has the threaded seat 25 formed therein to receive the threaded end of the nut carrier 26.- Within the carrier 26 is the pin-member 27 slidable'in said carrier. The pin-member 27'is mounted to yield, being spring actuated, which feature it has not been deemed necessary to illustrate in detail.

The pin 27 normally projects beyond the free end of the carrier 26 to engage the nut. The carrier 26 is slidable in the opening 31 in the frame 32. This frame 32 carries the nut-magazine 33 by which the nuts are fed one by one so as to be brought into register with the openings 31. At the upper end of the magazine 33 is the hopper 34 into which thenuts are fed.

The shutter 35 is hinged to the nutmagazine and normally acts to close the outlet of the magazine when the carrier is in retracted position, a spring 37 being connected to said shutter and the frame 32 for holding the shutter closed.

Mounted in bearings 40 on the standard 39 is a sprocket-wheel 41, said sprocketwheelhaving the central bore 42 which formsa seat for the hollow nut holder 43. This nut holder is composed of two parts inserted separately within the bore 42 of the sprocket; .It will not be necessary to illustrate this specially constructed nut-holder in detail as it is fully set forth in my said patent and forms no part of the present invention.

The sprocket wheel 41 is connected up to the sprocket wheel on the shaft 3 by the sprocket chain 51. The sprocket wheel 50 is loosely mounted on the shaft 3 and is held between the plate 52 and the ball-bearing collar 53. The spring 5% on the shaft 3 bears against the ball-bearing collar and is interposed between said collar and the sleeve 55 which is keyed on the shaft 3 so as to be longitudinally movable thereon but non-rotating on the said shaft. The sleeve has the graduated scale 56 thereon for determining the compression to be given to the spring 54- and by means of which the screwing-on pressure is controlled 01' regulated.

The inner end of the sleeve 55 has the threaded portion 57 which is engaged by the threaded portion 58 of the outer sleeve 59. The outer sleeve 59 is provided with the seat 60 to receive a tool for rotating said outer sleeve 59 and thereby advancing or withdrawing the inner sleeve 55. Secured to the shaft 3 is the collar 61,, said collar havingthe thumb screw 62 with its inner endadapted to enter a seat 63 in the outer sleeve 59 to prevent the accidental rotation of said sleeve 59 when it has been once set to adjust the inner sleeve 55.

It will be apparent from the above that the tension of the spring 54 may be controlled by advancing or withdrawing the inner sleeve55 and the amount of such increased or decreased compression of the spring will be indicated by the scale 56. In this manner, with great accuracy the pressure exerted on the sprocket-wheel 50 is controlled so as to cause said sprocket wheel to slip or turn on the shaft 8 when the resistance offered to said screwing-on pressure, which is transmitted by the said spring to the nut, is greater than said pressure.

Mounted on the guide 64 on the bed 2 is the slide 65 which carries the frame 66. This frame 66 supports the bolt magazine 67 to which the bolts are fed from a suitable hopper not shown. The bolts are fed one b one trom the hopper to the magazine 61 and the threaded shanks of the bolt project out beyond the magazine, as clearly shown in Fig. 1. The mechanism for delivering the bolts one by one to the position for applying the nuts has not been illustrated in detail as it forms no part of my present invention.

In the operation of the machine the nuts are fed to the nut magazine and the bolts to the bolt magazine one by one. With the nut and bolt in the positions indicated in Fig. 1,.power is applied to the shaft 3 and, through the action of the cam 15, the slideblock 19v will be advanced and provision is also made for simultaneously advancing the frame 66. The movement of the slideblock 19 advances the nut carrier 26 carrying with it the pin-member 27. The pinmember 27 enters the opening in the nut and the nut is moved from the magazine, the shutter 35 yielding to allow for the passage of said nut. In this manner the nut is advanced into the nut holder and as said nut holder is rotating with the sprocket ll the rotary movement is imparted to the nut when in the squared seat 49, which screws the nut on to the bolt.

As previously stated the amount of screwing-on pressure required to advance the nut on to the bolt, say from three to four turns as in a track-bolt, is predetermined and the sleeve 55 is adjusted so to compress the spring 54 to give the required screwing-on pressure. Accordingly when the sleeve 55 has been moved so that the scale indicates the degree of pressure which the spring exerts, which will be the required screwingon pressure, the operator knows that if the nut and bolt have been threaded properly the nut will be advanced on to the bolt between three and tour turns of the nut and that the resistance ofi'ered after the nut is advanced this far on the bolt will be such that thesprocket wheel 50 will slip on the shaft 3 and further rotation of the nutholder ceases. As a consequence, the nut is not screwed up so tight or so far on the bolt as not to be capable of being removed by hand. In this manner, by regulating the screwing-on pressure with great accuracy, the distance that the nut is screwed on the bolt may be accurately controlled so that an inspector, when he examines the trackbolt, can tell at a glance, whether when the wrench is applied to screw the nut onto its final position on the bolt, it will screw on with sufficient resistance to hold when finally seated.

Heretotore no machine has been devised for providing for a screwing-on pressure of constant degree and causing the screwing-on pressure to cease when said pressure is opposed by resistance to the advance of the nut greater than said pressure.

In Figs. 3 and a I have illustrated a modified form of my invention in which provision is made for allowing the bolt to yield when the resistance is greater than the screwing-on pressure. In this case the ordinary oblong enlargement 69 adjacent the head 70 of the bolt is adapted to bear against a yieldable finger 72 of the crank arm 73 pivoted at 74. A rod 75 is connected to said crank-arm and a spring 76 on said rod is interposed between the plate 77 and the abutment 78. The graduated pin 79 on the plate 77 passes up through an opening in the abutment 78.

It is apparent that provision might be made bolts, comprising a bolt holder, means for moving the holder to carry a bolt to nut receiving position, a member for supporting a nut in sorewlng-on position, means for feeding nuts to said member, yieldable means for effecting relative rotary movement of the nut and the bolt, and means for rendering said yieldable means ineffective to cause further relative rotation, when a predetermined degree of resistance to screwing-on pressure is present.

2. In a machine for assembling nuts and bolts, the combination with means for feed ing nuts one by one, a rotatable support for receiving said nuts and holding them in screwing-on position, a bolt holder, means for moving said holder to carry a bolt to nut receiving position, means for rotating said nut support, and means controlled by the resistance offered to the advance of the nut on the bolt for rendering said rotating means inoperative to further advance the nut.

3. In a machine for assembling nuts and 7 bolts, the combination with a rotatable member for supporting a nut in screwing-on posi tion, a support for a bolt, means for moving a bolt carried by said support to nut receiving'position, means for rotating said rotatable member, yieldable driving means for said member, and adjustable means for varying the pressure exerted by said driving means to render the same inoperative when the resistance to screwing on movement reaches a predetermined degree.

In testimony whereof, I, the said HANSON THOMAS, have hereunto set my hand.

HANSON THOMAS. 

